A General Purpose Transpiler for Fully Homomorphic Encryption

Fully homomorphic encryption (FHE) is an encryption scheme which enables computation on encrypted data without revealing the underlying data. While there have been many advances in the field of FHE, developing programs using FHE still requires expertise in cryptography. In this white paper, we present a fully homomorphic encryption transpiler that allows developers to convert high-level code (e.g., C++) that works on unencrypted data into high-level code that operates on encrypted data. Thus, our transpiler makes transformations possible on encrypted data. Our transpiler builds on Google's open-source XLS SDK (https://github.com/google/xls) and uses an off-the-shelf FHE library, TFHE (https://tfhe.github.io/tfhe/), to perform low-level FHE operations. The transpiler design is modular, which means the underlying FHE library as well as the high-level input and output languages can vary. This modularity will help accelerate FHE research by providing an easy way to compare arbitrary programs in different FHE schemes side-by-side. We hope this lays the groundwork for eventual easy adoption of FHE by software developers. As a proof-of-concept, we are releasing an experimental transpiler (https://github.com/google/fully-homomorphic-encryption/tree/main/transpiler) as open-source software

2023 EELS field tests at Athabasca Glacier as an icy moon analogue environment

JPL is developing a versatile and highly intelligent Exobiology Extant Life Surveyor (EELS) robot that would enable access to subsurface oceans and near-surface liquid reservoirs through existing conduits, such as the vents at the south pole of Enceladus or the putative geysers on Europa. A key mobility requirement for future vent exploration missions will be the ability to carefully descend and hold position in the vent to collect and analyze samples while withstanding plume forces without human intervention. Furthermore, this must be accomplished in a highly uncertain environment, requiring versatile hardware and intelligent autonomy. To work towards that goal, we have prototyped the EELS 1.0 and EELS 1.5 robots for horizontal and vertical mobility, respectively, in icy terrain. Autonomous surface mobility of EELS 1.0 was previously validated in a variety of terrain, including snowy mountains, ice rinks, and desert sand. Vertical mobility of EELS 1.5 was developed on laboratory ice walls. This paper presents the first mobility trials for both robots on large-scale, natural icy terrain: the Athabasca Glacier located in Alberta, Canada, a terrestrial analogue to the surfaces and subsurfaces of icy moons. This paper provides a preliminary written record of the test campaign’s four major trials: 1) surface mobility with EELS 1.0, 2) vertical mobility with EELS 1.5, 3) science instrument validation, and 4) terramechanics experiments. During this campaign, EELS 1.5 successfully held position and descended ~1.5 m vertically in an icy conduit and EELS 1.0 demonstrated surface mobility on icy surfaces with undulations and slopes. A miniaturized capillary electrophoresis (CE) instrument built to the form factor of an EELS module was tested in flowing water on the glacier and successfully demonstrated automated sampling and in-situ analysis. Terramechanics experiments designed to better understand the interaction between different ice properties and the screws that propel the robot forwards were performed on horizontal and vertical surfaces. In this paper we report the outcomes of the four tests and discuss their implications for potential future icy missions. The field test also demonstrated EELS’s ability to support Earth science missions. Another potential near-term follow-on could be a technology demonstration on the Moon. This paper is a high level report on the execution of the field test. Data and results will be detailed in subsequent publications